DOLICHOECTATIC INTRACRANIAL-ARTERIES - DI AGNOSIS AND THERAPY

Dolichoectasia of intracranial arteries is an infrequent disease with an incidence less than 0.05% in general population(10). It represents 7% of all intracranial aneurysms(56). Commonly seen in middle age pati ents with severe atherosclerosis and hypertension, the affected arteri es include the basilar artery, supraclinoid segment of the internal ca rotid artery, middle, anterior and posterior cerebral arteries; males are more frequently affected. The clinical features of these fusiform aneurysms are divided in three categories: ische-mic, cranial nerve co mpression and signs from mass effect. Hemorrhage may also occur(10-58) . Nine patients with symptomatic cerebral blood vessel dolichoectasias are presented. Six of them were males with moderate or severe hyperte nsion. Lesions were confined to the basilar artery in 3 cases, carotid arteries and the middle cerebral artery in 1 case, and both systems w ere affected in 4 patients. Middle cerebral arteries were affected in 5 cases and the anterior cerebral artery in one. An isolated fusiform aneurysm of the posterior cerebral artery is also presented (case 8) ( Table 3). Motor or sensory deficits, ataxia, dementia, hemifacial spas m and parkinsonism were observed. One patient died from cerebro-mening eal hemorrhage (Table 2). All patients were studied with computerized axial tomography of the brain, 5 cases with four vessel cerebral angio graphy, 4 cases with magnetic resonance imaging (MRI) and case 5 with MRI angiography. Clinical symptoms depend on the affected vascular ter ritory, size of the aneurysm and compression of adjacent structures. T he histopathologic findings are atheromatous lesions, disruption of th e internal elastic membrane and fibrosis of the muscular wall. The res ultant is a diffuse deficiency of the muscular wall and the internal e lastic membrane(61). Recent advances in neuroimaging such as better re solution of CT scan, magnetic resonance images (MRI) and MRI angiograp hy increased the diagnosis of this pathology showing clearly the affec ted vessels. This avoids the use of conventional or digital subtractio n angiography, reserved only for diagnosing suspected saccular aneurys m, evidence of subarachnoid hemorrhage or planning surgical treatment. The treatment of this entity may be medical or surgical. There is evi dence suggesting a more favorable outcome with anticoagulation therapy , although antiaggregation is a reasonable alternative(15). In our exp erience no difference in clinical outcome was evident(7). Surgical tre atment of this type of aneurysm includes intra-or extracranial occlusi on of parent artery, clipping or aneurysm trapping, tourniquet occlusi on, and circumferential wrapping with clip reinforcement. Endovascular occlusion has been accomplished with detachable balloon technique or coils(2, 3, 12, 41). No surgical attempt was done in our cases. The pr ognosis is variable depending on the patients age, vessels involved an d clinical complications. In our experience clinical outcome was mostl y unfavourable despite medical treatment.